By: Jaelyn Aleise, contributing intern (@_JaeAleise_) During training camp, the Dallas Cowboys have sported helmet decals reading “Arm In Arm” to show support for Dallas Police officers who were killed during the sniper attack in July. The design of the decals promotes unity between the Dallas Police Department and the citizens of Dallas. The team held a “unity ceremony” on the opening day of camp, where Dallas police chief David Brown, Mayor Mike Rawlings, and family members of slain officers walked arm-in-arm with Cowboys players, coaches and executives to show solidarity. Unfortunately, the NFL has decided that those decals will stay in training camp and not be permitted during the regular season. The NFL, like other professional sports leagues, has a very strict uniform policy and rarely makes exceptions. Examples include Brandon Marshall, who was fined for wearing green shoes to raise awareness for mental health issues, and DeAngelo Williams who was fined for have “Find the cure” printed on his eye black in honor of his mother who passed away from breast cancer. On Wednesday, the NFL told Cowboys vice president Jerry Jones that the team could not wear anything that is not in compliance with the NFL uniform policy. “Everyone has to be uniform with the league and the other 31 teams. We respect their decision,” Jones told the Dallas Morning News. “There are so many wonderful, wonderful causes, the league has to be careful. If you allow one, then what do you do about every team that has a great reason to have something on their helmets?” Just recently, WNBA players found themselves in a similar situation when the Indiana Fever, New York Liberty, and Phoenix Mercury and their players were fined for wearing all black warm-up shirts for citizens and police involved in recent shootings. After receiving lots of backlash, however, WNBA president Lisa Borders rescinded the penalties shortly after. Nonetheless, the NFL is very unlikely to change their decision. Photo credit: Getty Images